1. Field of the Invention
This invention relates to a satellite antenna alignment device and more particularly to an alignment device which enables a satellite antenna to be aligned with respect to a pair of satellites to enable the satellite antenna to properly receive the signals from both of the satellites.
2. Description of the Related Art
Satellite antennas are frequently used by owners of television sets to receive the signals from a particular satellite. In recent years, the small satellite antennas have become increasingly popular. Many different companies provide satellite television services such as DISH Network(trademark), PRIMESTAR(trademark), DIRECT TV(trademark), etc. In most cases, each of the companies utilizes a particular satellite to transmit signals to their customers. In order for the satellite antennas to receive the signals from the satellite, it is necessary that the antenna be properly aligned with respect to the associated satellite. Generally, the satellite antennas have a low noise block amplifier with integrated feed (LNBF) mounted on the end of a support arm so that the antenna dish will collect and focus the satellite signal onto the LNBF. Frequently, the manufacturer of satellite antennas will provide alignment information to the installers with that information being related to particular zip codes. For example, if a satellite antenna is going to be used with the DISH Network(trademark) and is going to be used in zip code 68118, the manufacturer will advise the installer that the dish of the antenna must be directed or aimed along compass heading or azimuth 207 degrees and must be elevated upwardly from the horizontal 37 degrees.
Electronic devices have been provided for use in aligning satellite antennas which measure the strength of the satellite signals. However, it is necessary for the antenna to be generally aligned with the satellite before those electronic devices will function properly. The alignment of the satellite antennas frequently requires that at least two people be involved and the same is costly and time-consuming. In most satellite antennas, when viewed from the top or bottom thereof, i.e., a vertical plane, the LNBF support arm extends transversely from the dish. Thus, if the dish is aligned or aimed along a particular compass heading, the LNBF support arm will also extend along that same compass heading, but will not point directly at the satellite, since it does not extend from the dish at a right angle when viewed from the side. Normally, when viewed from the side, the plane of the dish and the LNBF support arm form an acute angle. In other words, the dish may be elevated 37 degrees from the horizon but the support arm may be elevated 44 degrees or so, depending upon the particular antenna.
In some cases, the installer attempts to manually align the antenna along the proper compass heading by holding a compass some distance below or above the support arm and then attempts to align the support arm along the proper compass heading. This procedure is crude, at best, and the metal construction of the support arm frequently interferes with the normal operation of the compass. Further, it is extremely difficult for the installer to elevate the dish to the proper elevation, after being directed along the proper azimuth, so that the antenna will be properly aligned.
In an effort to solve the problems of the prior art enumerated above, applicant previously invented a satellite antenna alignment device which is the subject of U.S. Pat. Nos. 6,081,240 and 5,977,922. Although the device of the previously identified patents works extremely well when the antenna is being aligned with a single satellite, certain satellite antennas are now designed to receive signals from the satellites positioned at 110 degrees west longitude and 119 degrees west longitude. In those antennas designed to receive signals from two satellites, the antenna must have a pair of low noise block amplifiers with integrated feed (LNBF) which are mounted on the end of an elongated support arm. The inner end of the elongated support arm is normally secured to a dish mounting bracket which is selectively movably mounted on a skew scale. The skew scale is mounted on a mast clamp which is secured to the upper end of a mast clamp. The mast clamp may be pivotally moved with respect to the mast to change the elevation of the antenna. The skew plate and dish mounting bracket may be rotated with respect to the mast so that the azimuth (direction) of the antenna may be changed. Further, the dish mounting bracket may be rotatably moved with respect to the skew plate to rotate the dish or antenna. Although the conventional satellite antennas which are used to receive signals from a pair of satellites include elevation and skew scales provided thereon, those scales are not completely accurate. Further, for the elevation and skew angles to be accurate, the upper end of the mast must be perfectly plumbed in a vertical condition. If the upper end of the mast is not perfectly plumb, the elevation and skew angles scales will be dramatically inaccurate.
An alignment device is provided for a satellite antenna which is adapted to receive signals from two different satellites. The antenna includes a mast assembly, a support arm extending outwardly and upwardly from the mast assembly with a pair of LNBFs mounted on the outer end thereof, and a dish operatively secured to the support arm for movement therewith. The antenna alignment device of this invention is operatively removably secured to the amplifier support arm and includes a plumb bob which is positioned above a chart which indicates elevation and skew angles. The chart is somewhat parabolically-shaped so that the lower end of the plumb bob will be positioned closely adjacent the upper surface of the chart as the support arm is elevated and skewed. In another embodiment of the invention, the satellite antenna alignment device is placed against the face of a flat dish.
It is therefore a principal object of the invention to provide an improved satellite antenna alignment device.
A further object of the invention is to provide a satellite antenna alignment device which may be used with satellite antennas which receive signals from at least two satellites.
Still another object of the invention is to provide a satellite antenna alignment device which enables the satellite antenna to not only be accurately elevated, but also accurately skewed.
These and other objects will be apparent to those skilled in the art.